Rotary motor driven rotary switch



Dec. 20, 1960 H. F. MASON ROTARY MOTOR DRIVEN ROTARY SWITCH Filed Jan. 11, 1960 3 Shets-Sheet 1 IN l EN TOR HOWA 20 F MASON 5y H/S ATTORNEYS HARE/5, K/ECH, RUSSELL (2 K52 Dec. 20, 1960 MASON 2,965,725

ROTARY MOTOR DRIVEN ROTARY SWITCH Filed Jan. 11, 1960 3 Sheets-Sheet 2 //v l/ENTOR Hon A20 FT MASON Dec. 20, 1960 MASON 2,965,725

ROTARY MOTOR DRIVEN ROTARY SWITCH FiledJan. 11, 1960 s Sheets- Sheet 5 N 1/5 A/ TO? HOWA 90 F MA SON BY MS Arm/wars Hmzzvs, K 050/, P055541. (3* KEEN United States Patent 83cc ROTARY MOTOR DRIVEN ROTARY SWITCH Howard F. Mason, Los Angeles, Calif., assignor to Mason Electric Corporation, Los Angeles, Calif., a corporation of California Filed Jan. 11, 1960, Ser. No. 1,497

12 Claims. (Cl. 200-26) The present invention relates in general to rotary switches and, more particularly, to a rotary switch which is similar to and achieves the results attainable with the switches disclosed and claimed in my copending application Serial No. 710,796, filed January 23, 1958. The

rotary switch of the present invention also embodies fea-' tures disclosed in my Patents Nos. 2,831,073, 2,831,081 and 2,831,082, all granted April 15, 1958.

For convenience, the invention will be disclosed herein as embodied in a rotary reversing switch. However, it maybe embodied in a rotary stepping switch as well.

i As background requisite to an understanding of the invention, a rotary switch constructed in accordance with the teachings of the aforementioned patents and application includes an annular contact path having thereonv circumferentially spaced pairs of stationary contacts which are provided therein with radially inwardly facing recesses, the stationary contacts of each pair being spaced apart axially of the contact path. Rollable along the contact path and receivable in each pair of recesses therein is a shorting roller contact adapted to bridge the stationary contacts of each pair. The roller contact is mounted on a contact carrier which is movable along a carrier path adjacent and parallel to the contact path and which is spring biased toward the contact path so as to constantly urge the roller contact into engagement with the contact path. The contact carrier is mounted on an annular rotor which is disposed within the contact path and which is movable about the center of curvature thereof. Disposed within the rotor is a rotary actuator which drives the rotor through a resilient lost-motion connection capable of transmitting rotary movement of the actuator to the rotor only after limited rotary movement of the actuator relative to the rotor, the actuator and the rotor being provided with interengageable kicking means for initiating rotary movement of the rotor after a predetermined amount of energy has been stored in the resilient lost-motion connection. With the foregoing construction, the roller contact is detented in each of its operating positions and remains in the correspond ing pair of recesses until the limit of the lost-motion connection between the actuator and the rotor is reached. The roller contact is then forced out of the recesses in which it is disposed, whereupon the energy stored in the resilient lost-motion connection causes the roller contact to roll extremely rapidly along the contact path into the next pair of recesses.

A primary object of the invention is to provide a rotary switch of the foregoing nature wherein the actuator is annular and is driven by a rotary motor disposed within the annular actuator to provide an extremely compact, self contained rotary switch and motor drive combination.

An important object is to provide a rotation transmitting means or coupling means interconnecting the motor-and the actuator which does not engage until the motor has accelerated sutficiently to provide the maximum torque it is capable of delivering.

Another object is to provide a rotation transmitting The peak torque applied to the actuator is utilized to stress the resilient connection between the actuator and the rotor to store energy therein, which stored energy causes the switch to step to its next position after the roller contact has been forced out of the recesses in which it is disposed.

Another object is to incorporate a resilient lost-motion connection in the rotation transmitting means or coupling means between the motor and the actuator which serves as a centering means for the motor.

The foregoing construction permits the use of a very small motor easily capable of being housed within a rotary actuator of very small dimensions to minimize the overall dimensions of the rotary switch and rotary motor combination, which is an important feature.

The foregoing objects, advantages, features and re sults of the present invention, together with various other objects, advantages, features and results thereof which will be evident to those skilled in the rotary switch art in the light of this disclosure, may be achieved with the exemplary embodiment of the invention described in detail hereinafter and illustrated in the accompanying drawings, wherein:

Fig. 1 is a longitudinal sectional view of a rotary motor driven, rotary switch which embodies the inven-' tion;

Figs. 2 and 3 are transverse sectional views respectively taken along the arrowed lines 2-2 and 33 of Fig. 1; and

Figs. 4 to 9 are semidiagrammatic transverse sectiona views similar to Fig. 3 and illustrating the operation of the invention.

In the drawings, the numeral 10 designates a rotary switch which is driven by a rotary electric motor 12 disposed therewithin through a coupling means or rotation transmitting means 14 of the invention. While the rotary switch 10 is referred to herein in the singular, it will be understood that two or more such switches may be uti-v lized in end-to-end relation, as suggested in Fig. l of the drawings. For convenience, however, the invention will be considered herein as applied to but the one rotary switch 10 positively illustrated in the drawings, with the understanding that any additional rotary switches 10 operate in and are actuated in the same manner.

The rotary switch 10 is basically similar to that illustrated in Figs. 5 to 15 of the drawings of the aforementioned copending application, and is also basically similar to certain of the switches disclosed in the aforementioned patents. Consequently, the rotary switch 10 will not be described in complete detail herein, but only to the extent necessary to provide a clear understanding of the present invention.

The rotary switch 10 includes an annular, non-conducting housing 16 which is disposed in end-to-end relation with the corresponding housing of the next rotary switch,

if any, in the series. 16, or the ends of the end-to-end series of such annular housings if there be more than one rotary switch 10; are closed by annular partitions 18. annular partitions 18 and closing one end of the rotary motor, rotary switch combination is an end cap 20. Similarly, the other end of the rotary motor, rotary switch combination is closed by a housing 22 engaging the other annular partition 18, the housing 22 containing the con 7 pling means 14, as hereinafter described. The annular switch housing or housings 16, the annular partitions 18,--

the end cap 20 and the end housing 22 are heldin assemt,

Patented Dec. 20,1960,

The ends of the annular housing Engaging one of the bled relation by studs 24 threaded into the end housing 22 and having threaded thereon nuts 26 which are seated against the end cap 20.

The .annular housing 16 of the rotary switch .provides internally thereof an annular contact path 30 hav ing thereon circumferentially spaced pairs of axially spaced stationary contacts 32, such contacts being provided entirely within the confines thereof with radially inwardly facing recesses. Nonconducting .segments 34 of the contact path 30 separate the circumferentially spaced pairs of stationary contacts 32, such segments being circum-ferentially aligned with the spaces between the stationary contacts of the pairs so that metal tracking circumferentially from one stationary contact to another is impossible.

Roller contacts 36 are rollable along the contact path 30 and are receivable in the pairs of recesses in the pairs of stationary contacts 32, thereby positively detenting the rotary switch 10 in its operating positions. The roller contacts 36 are shorting rollers which bridge the spaces between the stationary contacts 32 of the pairs, thereby providing double makes and breaks. The relation between the number of pairs of stationary contacts 32 and the number of roller contacts 36 depends on the use to be made of the rotary switch 10. In the particular construction illustrated, the roller contacts 36 are moved back and forth through angles equal to the angular spacings of the stationary contact pairs by the rotary motor 12, the latter being a reversible motor in this instance. Consequently, the number of roller contacts 36 is equal to half the number of pairs of stationary contacts 32, although this applies only to the particular construction illustrated.

It will be noted that the pairs of stationary contacts 32 are relatively widely spaced circumferentially and that, as hereinbefore pointed out, metal tracking between the stationary contacts by the roller contacts 36 is impossible, due to the fact that the nonconducting segments 34 and the stationary contacts are circumferentially misaligned. These factors, plus such other factors as utilizing the roller contacts 36 as shorting rollers, provide for complete isolation from each other of the various external circuits connected to the stationary contacts, which external circuits depend on the use to be made of the rotary switch 10.

It will also be noted that the stationary contacts 32 and the roller contacts 36 are relatively massive, which enables them to withstand satisfactorily the impact forces resulting when the roller contacts drop into the pairs of recesses in the pairs of stationary contacts. Such impact forces are quite high since high contact pressures are maintained by biasing the roller contacts 36 toward the contact path 30 in a manner to be described.

The roller contacts 36 are flexibly mounted on axles 38 in such a manner that the contact pressures between the roller contacts and the pairs or" stationary contacts are uniform and self-equalizing, as discussed in more detail in the aforementioned Patent No. 2,831,082. The roller contacts 36 are housed in arc-quenching contact carriers 40 having recessed end walls, Fig. 1, receiving the ends of the axles 38.

The rotary switch it) includes an annular rotor 42 disposed within and concentric with the annular housing 16 and carrying the contact carriers 49. More particularly, the contact carriers 41 are radially movable in radial grooves 44, Fig. 1, in annular plates 4-6 forming theends of the rotor. The contact carriers 40 are resiliently biased toward the contact path 30 by pressure springs 48 which maintain the roller contacts 36 in engagement with the contact path 30. The pressure springs 43 provide high contact pressures between the roller contacts 36 and the stationary contacts 32 to minimize electrical resistance and to maximize heat dissipation by conduction. Also, the high :contact pressures provided 'by the pressure :springs 48 positively detent the roller :contacts 36inithezpairs of recesses in .the :pairs of stationary .con-

tacts 32 until such time as the roller contacts are forced out of the pairs of recesses in a manner to be described."

With the roller contacts 36 detented in their operating positions in this manner, teasing is impossible, even under the influence of vibration providing extremely high accelerations.

The pressure springs 48 are shown as torsion springs which are coiled around pins 50 and which react against pins 52 shown as located radially inwardly of the pins 50, the pins 50 and 52 extending between and interconnecting the annular plates 46 of the rotor 42. The manner in which the pressure springs 48 are mounted on the rotor 42 and the manner in which they act on the contact carriers 40 are fully described in the aforementioned copending application so that a further description herein is thought to be unnecessary.

It will be noted that the rotor 42 is, in effect, journaled in the annular housing 16, the roller contacts 36 and the annular contact path 30 providing a bearing means for the rotor. Friction during rotary movement of the rotor, i.e., while the roller contacts 36 are on the nonconducting segments 34 intermediate the pairs of stationary contacts 32, is minimized due to the fact that the roller contacts 36 are axle-mounted rollers or wheels. In this connection, it will be noted that the axles 38 are of small diameter compared to the roller contacts 36 so as to render the roller contacts freely rollable along the contact path .30.

Disposed within and concentric with the rotor 42 is an annular rotary actuator 54 within which the reversible electric motor 12 is concentrically disposed. The annular actuator 54 is a sleeve or tube one end of which is rotatably mounted on the end cap 20 and the other end of which is connected to the motor 12 through the coupling means 14 in a manner to be described hereinafter.

Rotary movement of the rotor 42 to move the roller contacts 36 between their operating positions is produced by the actuator 54 through a rotation transmitting means 56 which provides a resilient lost-motion connection between the actuator and the rotor. With this construction, the roller contacts 36 are detented in the pairs of recesses and the pairs of stationary contacts 32 until the limit of the resilient lost-motion connection is reached, whereupon the roller contacts 36 are camrned out of the pair of recesses in which they are disposed by the portions of the pairs of stationary contacts which form the sides of such recesses. The energy stored in the resilient lost-motion connection then causes the roller contacts to roll extremely rapidly along the contact path 30 into the next pairs of recesses, the roller contacts in effect jumping to the next pairs of recesses.

Considering the rotation transmitting means 56 and the aforementioned resilient lost-motion connection provided thereby, it includes advancing springs 58 mounted on the rotor 42 and engaging the actuator 54. construction illustrated, the advancing springs 58 are torsion springs coiled around the pins 51) and reacting against the pins 52. More particularly, the advancing springs 58 have arms 69 seated against the pins 52 and have other arms 62 extending generally radially inwardly into apertures 64 in the actuator 54. For a more detailed description of the manner in which the advancing springs 58 are mounted on the rotor 42, attention is directed to the aforementioned copending application.

The advancing springs 58 are divided into two groups, the advancing springs of the respective groups being uniformly distributed circumferentially of the rotor 42. and being oppositely oriented. Such opposite orientations are best illustrated in Figs. 4 to 9, wherein two oppositely oriented advancing springs are shown. Considering Fig. 6, for example, when the actuator 54 is rotated relative to the rotor 42 in the clockwise direction, the left advancing spring 53 is stressed to store energy therein. As will be apparent, the left advancing spring 53 is stressed because of the fact that an edge of the aperture 64 which in the receives the arm 62 moves such arm away from the arm- 60, the latter being restrained bythe corresponding pin 52. At the same time, the right advancing spring 58 shown in Fig. 6 acts as a kicking means for transmitting rotation of the actuator 54 to the rotor 42, so as to kick the roller contacts 36 out of the pairs of recesses in which they are disposed, after the limit of the lost-motion connection between the actuator 54 and the rotor 42 is reached. As will be apparent, this kicking action results when an edge of the aperture 64 which receives the arm 62 of the right advancing spring 58 forces such arm against the corresponding pin 52 on the rotor 42.

When the direction of rotation of the actuator 54 is reversed, the right advancing spring 58 of Fig. 6, for example, is stressed to store energy therein and the actuator cooperates with the left advancing spring 58 to form the kicking means for initiating rotation of the rotor 42 to force the roller contacts 36 out of the pairs of recesses in which they are disposed. Thus, for one direction of rotation of the actuator 54, the advancing springs 58 of one set or group are stressed and the advancing springs of the other set or group act as kickers, the reverse being true for the opposite direction of rotation of the actuator. vanciug springs 58 cooperate to provide kicking means is more fully set forth in the aforementioned copendingj application. I

Considering the manner in which the reversible 'electric motor 12 is connected to the rotary switch 10 by the coupling means 14, and referring particularly to Figs. 1 and 2 of the drawings, the motor, as hereinbefore indicated, is concentrically disposed within the actuator 54 and one end thereof is seated in a recess 66 in the end cap 20. The other end of the, motor 12 extends through and is secured to a wall 68 of the housing 22 which divides the interior of such housing into compartments 70 and 72. The compartment 72 is closed by a cover 74.

T he motor 12 is provided with a shaft 76 which extends axially into the compartment 72. Fixed on the shaft 76 within the compartment 72 is a U-shaped driving member 78 having arms 80 extending parallel to the axis of the motor and switch combination into circumcam member 84 which serves to center the motor 12 relative to the cam member 84. 1 The manner in which the spring 88 is stressed will be clear from Figs. 4 and of the drawings As will beapparent, when the shaft 76 starts to rotate, one of the arms 80 of the driving member 78 moves one of the spring arms 90 away from the other, the other being restrained by one of the cam elements 86. When the spring 88 is fully stressed, the arms 80 of the driving member 78 reach the ends of the circumferential slots 82 in the cam member 84 to initiate rotational movement of the cam member.

When the cam member 84 begins to rotate, the cam elements 86 thereon enter notches 92 in levers 94 which are connected to the housing 22 by pivots 96. The actuator 54 is provided with arms 98 which extend parallel to the axis of the device through arcuate slots 100 in the housing wall 68 into the notches 92 in the levers 94 at points located between the pivots 96 and the cam elements 86 when the cam elements are in the notches 92. Consequently, when the lost motion between the driving member 78 and the cam member 84 istaken up and the cam elements 86 enter the notches 92 in the levers 94 to pivot such levers, the levers rotate the actu- The manner in which the actuator 54 and theadmay be effected in any suitable manner.

positively detent the rotor in vides a torque multiplying means which multiplies the torque output of the motor 12.

Operation The operation of the rotary motor, rotary switch com-' bination of the invention will now be considered with particular reference to Figs. 4 to 9 of the drawings, these figures being semidiagrammatic views in which the structure has been simplified considerably, andsome com ponents omitted, for the sake of clarity.

In Fig. 4 of the drawings, the various components are shown at rest with the roller contacts 36 in one of their two sets of operating positions. It will be assumed that the rollers contacts 36 are to be displaced in the clockwise direction into the other set of operating positions.

The desired action is initiated by energizing the reversible motor 12 in a direction to drive the shaft 76 of the motor in the clockwise direction. Such energization lFOl' example, the'motor 12 may be controlled by an external switch, not shown. Alternatively, if the device of the invention is merely to cycle back and forth between the two sets of operating positions of the roller contacts 36, the

motor 12 may be controlled by the rotary switch 10 itself through suitable connections, not shown, to appropriate ones of the stationary contacts 32.

Initially, the motor 12 is under no load since the cam elements 86 on the cam member 84 are out of engagement with levers 94. Consequently, the motor is free to accelerate quickly to its maximum speed so as to provi-de its peak torque output, which is an important feature. 12 approaches or reaches its peak torque output, the cam elements 86 enter the notches 92 in the levers 94, whereupon the spring 88 is stressed -to store energy therein. When the limit of the lost-motion connection between the drive member 78 and the cam member 84 is reached, the cam elements 86 begin to pivot the levers 94 to cause such levers to begin to rotate the actuator 54, as

shown in Fig. 6 of the drawings.

7 Such rotation of the actuator 54 stresses one set of the advancing springs 58 to store energy therein and, ultiimately, the kicking means provided by the other set of advancing springs initiates rotation of the rotor 42. In other words, the rotor 42 starts to rotate when the resilient lost-motion connection represented by one set of the advancing springs 58 has been taken up.

Referring to Fig. 7, as the rotor 42 starts to rotate, the roller contacts 36 are cammed out of the pairs of recesses in the pairs of stationary contacts 32 in which they are disposed, this action taking place in opposition to the action of the pressure springs 48, which normally, the operatingposition in which it is disposed.

As soon as the roller contacts 36 leave the pairs of recesses in which they were disposed, the energy stored in the advancing springs'58 and in the spring 88 carries the rotor 42 to its next position. Consequently, the motor 12 may be deenergized at about the time the various components are in the positions shown in Fig. 7. Preferably, this is accomplished by connecting the motor in circuit with appropriate ones of the stationary contacts the pairs of recesses in the next pairs of stationary contacts, as shown in Figs. 7, 8 and 9 of the drawings. The

energy stored in the system causes this action to take place extremely rapidly, i.e., within a few thousandtlis'i of a second. While the rotor 42 is jumpingto its next position, the motor 12 is coasting to a stop, the

Referring to Fig. 5 of the drawings, as the motor -tnember 84 at this point being out of engagement with the levers 94. Ultimately, all of the components reach the positions shown in Fig. 9, which is the second rest position.

In order to return from the Fig. 9 position to the Fig. 4 position, it is merely necessary to energize the motor 12 in a direction 'to rotate the shaft 76 in the counterclockwise direction. The operation in response to reversed motor rotation is the same as hereiribefore described so that a repetition is not necessary.

As will be apparent, since the motor 12 is permitted to accelerate to its peak torque before any load is imposed thereon, and since this peak torque is multiplied by the levers 94 prior to application to the actuator '54, the motor 12 may be very small so that it may be housed within the actuator 54, as shown, to obtain a very compact rotary motor, rotary switch combination having minimum overall dimensions.

In order to permit manual shifting of the rotor 42 from one of its operating positions to the other, the arms 98 connected to the actuator 54, in addition to engaging the levers 94, also engage an operator member 102 rotatable about the axis of the device, the arms 98 extending into notches 104 in the operator member. The lat-ter member is provided with a central hub 106 which projects through the cover 74 and which is provided with a screw driver slot 108 therein.

Although an exemplary embodiment of the invention has been disclosed herein for purposes of illustration, it will be understood that various changes, modifications and substitutions may be incorporated in such embodiment without departing from the spirit of the invention as defined by the claims which follow.

I claim:

1. In a switch, the combination of: an arcuate contact path having a center of curvature and having circumferentially spaced recesses therein and having thereon'at least one stationary contact in which one of said recesses is formed; a contact carrier movable adjacent and parallel to said contact path; a roller contact carried by said contact carrier and engaging and movable along said contact path and receivable in each of said recesses; actuating means for moving said contact carrier adjacent and parallel to said contact path, said actuating means including a rotor movable about said center of curvature of said contact path and a rotary actuator movable relative to said rotor, said contact carrier being carried by said rotor; first rotation transmitting means interconnecting said rotor and said actuator and providing a resilient lost-motion connection therebetween for transmitting rotary movement of said actuator to said rotor after limited rotary movement of said actu ator relative to said rotor; a rotary motor; and second, torque multiplying, rotation transmitting means interconnecting said actuator and said motor and providing a resilient lost-motion connection therebetween for transmitting rotary movement of said motor to said actuator after limited rotary movement of said motor relative to said actuator.

2. In a switch, the combination of: an arcuate contact path having a center of curvature and having circumferentially spaced recesses therein and having thereon at least one stationary contact in which one of said recesses is formed; a contact carrier movable adjacent and parallel to said contact path; a roller contact carried by said contact carrier and engaging and movable along said contact path and receivable in each of said recesses; actuating means movable about said center of curvature of said contact path for moving said contact carrier a'djacent and parallel to said contact path, said actuating means including an annular rotor and an annular rotary actuator movable relative to said rotor about said center of curvature of said contact path, said contact carrier being carried 'by said rotor and said actuator being disposed within said rotor; firstrotation transmitting means interconnecting said rotor and said actuator and provid-- actuator; and second rotation transmitting means inter connecting said actuator and said motor for transmitting rotary movement of said motor to said actuator.

3. In a switch, the combination of: an arcuate contact path having a center of curvature and having circumferentially spaced recesses therein and having thereon at least one stationary contact in which one of said recesses is formed; a contact carrier movable adjacent and parallel to said contact path; a roller contact carried by said contact carrier and engaging and movable along said contact path and receivable in each of said recesses; actuating means movable about said center of curvature of said contact path for moving said contact carrier adjacent and parallel to said contact path, said actuating means including an annular rotor and an annular rotary actuator movable relative to said rotor about said center of curvature of said contact path, said contact carrier being carried by said rotor and said actuator being disposed within said rotor; first rotation transmitting means interconnecting said rotor and said actuator and providing a resilient lost-motion connection therebetween for transmitting rotary movementof' said actuator to said rotor after limited rotary movement of said actuator relative to said rotor; a rotary motor disposed within said actuator; and second, torque multiplying, rotation transmitting means interconnecting said actuator and said motor and providing a resilient lost-motion connection therebetween for transmitting rotary movement of said motor to said actuator after limited rotary movement of said motor relative to saidactuator.

4. In a switch, the combination of: an annular contact path having circumferential'ly spaced, radially inwardly facing recesses therein and having thereon at least one stationary contact at one of said recesses; an annular rotor within said contact path; a movable contact carried by said rotor and engaging and movable along said contact path and receivable in each of said recesses in response to rotary movement of said rotor; means carried by said rotor for biasing said movable contact into engagement with said contact path; an annular rotary actuator within said rotor; first rotation transmitting means interconnecting said rotor and said actuator for transmitting rotary movement of said actuator to said rotor; a rotary motor within said actuator; and second rotation transmitting means interconnecting :said actuator and said motor for transmitting rotary movement of said motor to said actuator.

5. In a switch, the combination of: an annular contact path having circumferentially spaced, radially inwardlyfacing recesses therein and having thereon at-least one stationary contact at one of said recesses; an an-- nu'lar rotor within said contact path; a movable contact carried by said rotor and engaging and movable along said contact path and receivable-in each of said recesses in response to rotary movement of said rotor; means carried by said rotor for biasing said movable contact into engagement with said contact path; an

annular rotary actuator within said rotor; first rotation transmitting means interconnecting said rotor and said:

actuator for transmitting rotary movement of said actuator to said rotor; a rotary motor within said actuator; and second, torque multiplying, rotation transmitting means interconnecting said actuator and said motor for transmitting rotary movement of said motor to said actuator.

6. In a switch, the combination of: an annular contact path having circumferentially spaced, radially in 'war'dlyfacing recesses therein and having thereon at least= one stationary contact at one of said recesses; an annular rotor within said contact path; a roller contact carried by said rotor and engaging and rollable along said contact path and receivable in each of said recesses in response to rotary movement of said rotor; means carried by said rotor for biasing said roller contact into engagement with said contact path; an annular rotary actuator within said rotor; first rotation transmitting means interconnecting said rotor and said actuator for transmitting rotary movement of said actuator to said rotor; a rotary motor within said actuator; and second rotation transmitting means interconnecting said actuator and said motor for transmitting rotary movement of said motor to said actuator.

7. In a switch, the combination of: an annular contact path having circumferentially spaced, radially inwardly facing recesses therein and having thereon at least one stationary contact at one of said recesses; an annular rotor within said contact path; a roller contact carried by said rotor and engaging and rollable along said contact path and receivable in each of said recesses in response to rotary movement of said rotor; means carried by said rotor for biasing said roller contact into engagement with said contact path; an annular rotary actuator Within said rotor; first rotation transmitting means interconnecting said rotor and said actuator and providing a resilient lost-motion connection therebetween for transmitting rotary movement of said actuator to said rotor after limited rotary movement of said actuator relative to said rotor; a rotary motor within said actuator; and second rotation transmitting means interconnecting said actuator and said motor for transmitting rotary movement of said motor to said actuator.

8. In a switch, the combination of: an annular contact path having circumferentially spaced, radially inwardly facing recesses therein and having thereon at least one stationary contact at one of said recesses; an annular rotor within said contact path; a roller contact carried by said rotor and engaging and rollable along said contact path and receivable in each of said recesses in response to rotary movement of said rotor; means carried by said rotor for biasing said roller contact into engagement with said contact path; an annular rotary actuator within said rotor; first rotation transmitting means interconnecting said rotor and said actuator and providing a resilient lost-motion connection therebetween for transmitting rotary movement of said actuator to said rotor after limited rotary movement of said actuator relative to said rotor; a rotary motor within said actuator; and second rotation transmitting means interconnecting said actuator and said motor and providing a resilient lost-motion connection therebetween for transmitting rotary movement of said motor to said actuator after limited rotary movement of said motor relative to said actuator.

9. In a switch, the combination of: an annular contact path having circumterentially spaced, radially inwardly facing recesses therein and having thereon at least one stationary contact at one of said recesses; an annular rotor within said contact path; a roller contact carried by said rotor and engaging and rollable along said contact path and receivable in each of said recesses in response to rotary movement of said rotor; means carried by said rotor for biasing said roller contact into engagement with said contact path; an annular rotary actuator within said rotor; first rotation transmitting means interconnecting said rotor and said actuator and providing a resilient lost-motion connection therebetween for transmitting rotary movement of said actuator to said rotor after limited rotary movement of said actuator relative to said rotor; a rotary motor within said actuator; and second, torque multiplying, rotation transmitting means interconnecting said actuator and said motor and providing a resilient lost'motion connection therebetween for transmitting rotary movement of said motor to said actuator after limited rotary movement of said motor relative to said actuator.

10. In a switch, the combination of: an annular contact path having circumferentially spaced, radially inwardly facing recesses therein and having thereon at least one stationary contact at one of said recesses; an annular rotor within said contact path; a roller contact carried by said rotor and engaging and rollable along said contact path and receivable in each of said recesses in response to rotary movement of said rotor; means carried by said rotor for biasing said roller contact into engagement with said contact path; an annular rotary actuator within said rotor; first rotation transmitting means interconnecting said rotor and said actuator and providing a resilient lostmotion connection therebetween for transmitting rotary movement of said actuator to said rotor after limited rotary movement of said actuator relative to said rotor; a rotary motor within said actuator; and second rotation transmitting means for transmitting rotary movement of said motor to said actuator after limited rotary movement of said motor relative to said actuator, including inter engageable means connected to said motor and said actuator and interengageable after limited rotary movement of said motor relative to said actuator.

11. In a switch, the combination of: an annular contact path having circumferentially spaced, radially inwardly facing recesses therein and having thereon at least one stationary contact at one of said recesses; an annular rotor within said contact path; a roller contact carried by said rotor and engaging and rollable along said contact path and receivable in each of said recesses in response to rotary movement of said rotor; means carried by said rotor for biasing said roller contact into engagement with said contact path; an annular rotary actuator within said rotor; first rotation transmitting means interconnecting said rotor and said actuator and providing a resilient lostmotion connection therebetween for transmitting rotary movement of said actuator to said rotor after limited rotary movement of said actuator relative to said rotor; a rotary motor within said actuator; and second rotation transmitting means for transmitting rotary movement of said motor to said actuator after limited rotary movement of said motor relative to said actuator, including interengageable means connected to said motor and said actuator and interengageable after limited rotary movement of said motor relative to said actuator, said interengageable means including cam means connected to said motor and said actuator, respectively.

12. In a switch, the combination of: an annular contact path having circumferentially spaced, radially inwardly facing recesses therein and having thereon at least one stationary contact at one of said recesses; an annular rotor within said contact path; a roller contact carried by said rotor and engaging and rollable along said contact path and receivable in each of said recesses in response to rotary movement of said rotor; means carried by said rotor for biasing said roller contact into engagement with said contact path; and actuating means for producing rotary movement of said rotor, including a rotary motor within said rotor, and including interengageable means for transmitting rotary movement of said motor to said rotor and interengageable after limited rotary movement of said motor relative to said rotor.

References Cited in the file of this patent UNITED STATES PATENTS 2,554,506 Schwarz May 9, 1951 2,565,863 Linn Aug. 28, 1951 2,680,163 Besserer June 1, 1954 2,831,181 Mason Apr. 15, 1958 FOREIGN PATENTS 612,509 Germany Apr. 26, 1935 

